Improvement in apparatus for the manufacture of white lead



UNIT

CHARLES J. SEVIN, OF NEWN YORK,

PATENT QF-rrcn Specification forming part of Letters Patent No. 151,165,dated May 19 1874; application filed May 9, 1874.

.To all whom it may concern Be it known that I, CHARLES JULIUs SEviN, ofthe city of New York, county and State of New York, have invented a newand useful Apparatus for the Manufacture of \Vhite Lead; and I do herebydeclare the following to be a full, clear, and exact descriptionthereof, which will enable those skilled in the art to make and use thesame, reference being had to the accompanying drawing, forming part ofthis specification, in which drawingl Figure 1 represents a sectionalplan of my apparatus. Fig. 2 is a longitudinal vertical section of thesame in the plane w 00, Fig. 1.

Similar letters indicate correspondin parts.

This invention relates to an apparatus for the manufacture of whitelead, in which two revolving drums are employed, which are supplied withgranulated lead and acetic acid, and through which is passed a currentof carbonic acid. The carbonic acid, before being admitted to thecorroding-drums, is heated, so as to increase its decomposing effect.The carbonic acid is produced by burning coke or other suitablematerial, and a pump serves to draw the same from the furnace through apurifier, and then to force it through a heater into thecorroding-drums. The surplus carbonic acid passes from thecorroding-drums into a mixer, which is supplied with a solution ofacetate of lead from a stationary corroding-vat.

In the drawing, the letter A designates a furnace, in which is producedcarbonic-acid gas by burning coke or other suitable material. Thecarbonic acid thus produced is impure, and in order to purify it I passit through one or more purifiers, B. This purifier is filled with purewater, or other suitable material, and from its bottom or side extends apipe, a, to the top of the furnace A, while a pipe, 12, which emanatesfrom the top of said purifier, connects with the suction port of adoubleacting pump, 0. The exhaust-port of this pump connects, by a pipe,0, with a coil, d, situated in the interior of a heater, D, which isheated by steam or otherwise. When the pump is set in motion, therefore,the carbonic E E; said pipe c being made to spread in two branches, eachof which passes into the hollow gudgeon f of one of the drums. Thegudgeons f f, at the receiving ends of the drums, connect, by pipes g 9extending through the entire length of the drums, with thedischarge-gudgeons h 71 and these pipes are provided with partitions i,(see Fig. 1,) and with holes j k on each side of these partitions, sothat the carbonic acid which is not used up in said drums passes throughthe holes R to the dischargegudgeons h h. From these gudgeons extendpipes l l to the mixer F, the object of which will be presently morefully explained. The drums E E are conical, being largest at the endssupported by the dischargegudgeons h h, and they are geared together bycog-wheels m a, the cog-wheel n being mounted on a shaft, 0, to which arevolving motion is imparted by steam or other suitable power. Each drumis provided with a discharge-openin g, 19, near its large end, and thesedischargeopenings are separated from the remaining spaces of said drumsby perforated partitions or sieves q.

The metallic lead from which the white lead is to be manufactured isgranulated by casting it in small pieces, like shot; it is then placedinto the drums E E, and a suitable quantity of vinegar or diluted aceticacid is added.

set in motion, and while the drums revolve a current of heated carbonicacid 1s forced through each of said drums. By the combonic acid, thelead is transformed into carbonate of lead, which, being insoluble inthe liquid contained in thedrums, is precipitated and caused toaccumulate in the large ends of the drums, the metallic lead beingprevented by the sieves g from passing to said large ends. At suitableintervals the white lead, together with the liquid, is drawn off fromthe drums, the white lead is allowed to precipitate, and the clearliquid is returned to the drums E E. The surplus carbonic acid, or thatportion of the carbonic acid which does not combine with the lead in thedrums E E, passes ofi' through the holes 70 in the pipes g g, andthrough the pipes Z 1 into the mixer F, which communicates by a pipe, r,with the corroding-vat G.

Then the drums are closed, and the shaft 0 is bined action of the aceticacid and of the can i This vat is filled with granulated lead anddiluted acetic acid, and the liquid acetate of lead formed therein'isallowed to pass into the mixer F, where it is brought in contact withthe carbonic acid escaping from the pipes. These pipes are provided withrose-heads s at their discharging ends, (see Fig. 2,) so that thecarbonic acid is spread and brought in intimate contact with the liquid;and in the mixer is an agitator, t, which serves to facilitate thecontact of the carbonic acid with the liquid.

By this apparatus I am enabled to convert metallic lead into white leadin less than eight hours; and the cost of the process is comparativelylittle, since the acetic acid can be used over and over again for a longtime.

The process of converting the lead into carbonate of lead is materiallyfacilitated by the heated carbonic-acid gas.

What I claim as new, and desire to secure by Letters Patent, is-

1. In an apparatus for the manufacture of white lead, the combination ofa carbonic-acid generator, one or more purifiers, a pump, a heater, andtwo revolving drums, receiving and discharging the heated carbonic acidthrough their hollow gudgeons, and provided with sieves to prevent themetallic lead from passing oil with the liquid, all constructed andoperating substantially in the manner and for the purpose herein shownand described.

2. The combination of amixer, I and a corroding-vat, G, with pipes l I,through which escapes the surplus carbonic acid from the drums E E,substantially as set forth.

CHARLES JULIUS SEVIN.

Witnesses W. HAUFF, JAMES L. NORRIS.

